Alkaline hydrolysis of the ether-soluble resin glycoside fraction of seeds of Quamoclit (Q.) x multifida, a hybrid between Q. pinnata and Q. coccinea, gave new glycosidic acids, multifidinic acids A and B, along with two known glycosidic acids, quamoclinic acid A and operculinic acid A, and three organic acids, (2S)-2-methylbutyric acid, n-decanoic acid and n-dodecanoic acid. Further, as major ether-soluble resin glycosides, new jalapins named multifidins I and II, were isolated accompanied by quamoclins I-IV, which were previously obtained from seeds of Q. pinnata. The structures of multifidins I and II, and multifidinic acids A and B have been determined on the basis of chemical and spectral data.